Investigating the Influence of Treated Sewage on Groundwater and Surface Water Using Wastewater Indicators in Berlin,Germany

摘要

Around 70% of Berlin's drinking water derives from bank filtration or artificial recharge.A major advantage of bank filtration is the capability of the subsurface to remove contaminants and save natural groundwater resources.Because the surface water contains elevated amounts of treated sewage,Berlin's system is a semi-closed water cycle relying partly on indirect wastewater reuse.A number of wastewater residues can be traced in the groundwater and serve as a tool to characterise the bank filtration systems.Conservative tracers such as some wastewater indicators and stable isotopes are used to estimate flow velocities and proportions of bank filtrate in the abstraction wells prior to reactive transport evaluations.Examples of tracer applications in the Berlin system are presented in this paper.In addition,an overview is given of results of various studies conducted on contaminant transport and their removal during underground passage of the bank filtrate in Berlin.